ARGUS/McCloskey's API index series has become a reference for coal trade and derivatives market pricing. According to ARGUS statistics, about 90% of the world's coal products and derivatives are priced by API 2 and API 4. API 2 is not only the benchmark for the pricing of coal entity transactions in Southern Europe, but also the pricing standard for OTC transactions. Futures exchanges in Europe and the United States have actively launched futures contracts related to API indexes. ICE and CME have listed futures contracts based on API 2, API 4, API 6 indexes, etc. CME's recently developed API 8 South China Steam Coal Futures Contract has expanded its market scope from the United States, Europe and Australia to China's coastal areas.

API 2 index is a CIF price index reflecting 6000 kcal/kg steam coal imported into Western Europe and Northern Europe through major European ports such as Amsterdam, Rotterdam and Antwerp. Argus and McCloskey, two coal trade market analysis companies, will respectively make statistics on the arrival freight of Amsterdam, Rotterdam and Antwerp ports and the quotations of the buyers and sellers of coal trade. Then the freight and the arrival coal price calculated according to the weighted average of trade volume are added to form the ARA price index. The average of Argus and McCloskey price indexes is the (API 2) CIFARA index.

CME Nordic three ports（ API 2 ） CIF price (ARGUS-McCloskey) futures